Air bag suspensions, as well as walking beam suspensions, are known in the prior art, but my invention combines these in a new and novel manner to provide an improved suspension.
In a tandem axle suspension, a pair of spaced wheel axles extend crosswise of the frame of the vehicle. Each axle supports a pair of wheels and each wheel is outboard of a respective one of a pair of channels which extend longitudinally of the vehicle and, with cross-braces, form the main frame of the vehicle.
In my improved suspension, a walking beam is pivoted intermediate its ends to a respective frame channel, and preferably parallel to but outboard of the same. Axle supports are respectively connected to a common end of each walking beam to support an axle therebetween. A support arm is pivotally associated with each of the other common ends of the walking beams, each arm having an axle portion connected thereto.
The support arms are disposed in spaced relation with respective ones of the other common ends of the walking beams, and an air bag is disposed between each support arm and the related end of the walking beam. Each walking beam is pivotally mounted on its related main frame channel, and the pivot therefor may be in the form of stub shafts secured to respective frame channels. However, to increase rigidity of the main frame, it is preferred to employ a shaft which extends between the pair of channels forming the frame, with opposite ends of the shaft journalled in bearings carried by respective channels. The walking beams may be mounted on the opposite shaft ends for independent pivotal movement, or they may be keyed to such opposite ends so that the shaft acts as a torsion rod.